Kinesthetic and Vestibular Senses (6A) Practice Test

A vestibular-kinesthetic integration study has participants walk on a treadmill while performing a head-turning task (left-right yaw) at a fixed tempo. In one block, the treadmill briefly accelerates and decelerates unpredictably; in another block, speed is constant. Participants cannot see their legs, and they must press a button when they detect that their step length has changed. Accuracy drops selectively during the unpredictable speed block, especially when head turns are required. Which outcome would best illustrate the integration of kinesthetic and vestibular senses?

A Reduced detection accuracy when vestibular signals from head motion and proprioceptive signals from gait provide competing information about self-motion.

B Improved detection accuracy during head turns because vestibular input replaces proprioceptive input for limb-position monitoring.

C No change in detection accuracy across blocks because step length is encoded only by vision, not by body-based senses.

D Reduced detection accuracy only in participants reporting higher frustration, indicating emotion is the primary determinant of kinesthetic perception.

In a clinical vignette, a patient recovering from an inner-ear infection reports that reading while riding in a car triggers nausea and a sense of "lag" when the head turns. The patient can walk normally in well-lit hallways but avoids escalators and reports irritability in busy environments. A therapist notes that symptoms worsen when the patient turns the head while keeping the gaze on a fixed target. Which explanation best accounts for the patient’s symptoms based on vestibular contributions to balance and perception?